SharePoint 2010 Reporting Services Integration Authentication Fix

Server 1 (WFE), Server 2 (APP & Central Admin), Server 3 (DB w/ Report Server) - NTLM install
 
In SharePoint Central Administration -- General Application Setting - Reporting Services Integration

Selected the RS URL and "Trusted Account", domain user name & password (Server 3, local admin domain account for RS access)

Everything will work fine including activation of the features on existing site collections BUT when you click on Set Server Defaults, you will end up getting The request failed with HTTP status 401: Unauthorized

Fix

KB article has the answer: http://support.microsoft.com/kb/871179/en-us

On Server 2 (App & Central Admin)

To work around this behavior if you have multiple application pools that run under different domain user accounts, you must force IIS to use NTLM as your authentication mechanism if you want to use Integrated Windows authentication only. To do this, follow these steps on the server that is running IIS:

1. Start a command prompt.
2. Locate and then change to the directory that contains the Adsutil.vbs file. By default, this directory is C:\Inetpub\Adminscripts.
3. Type the following command, and then press ENTER:
   cscript adsutil.vbs set w3svc/NTAuthenticationProviders "NTLM"
4. To verify that the NtAuthenticationProviders metabase property is set to NTLM, type the following command, and then press ENTER:
   cscript adsutil.vbs get w3svc/NTAuthenticationProviders
   The following text should be returned:

   NTAuthenticationProviders       : (STRING) "NTLM"

Happy Monday!

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